Since an aromatic polycarbonate is a resin material which not only is excellent in mechanical properties such as impact resistance but also is excellent in heat resistance, it has been widely used as materials for housings or parts of various computers such as desktop computers and notebook computers, printers, word processors, copying machines, and the like.
In recent years, with respect to a molded article formed of an aromatic polycarbonate, particularly in the case where it is intended to use the article as a housing, it has been strongly desired to reduce the thickness of the molded article for the purpose of reducing the weight thereof. Furthermore, since distortion by external stress or under the load of the parts inside the housing tends to occur when a thin housing is used, there has been a demand for aromatic polycarbonates having high stiffness and high dimensional precision.
In order to improve the stiffness and dimensional precision of an aromatic polycarbonate, a method has been attempted in which an inorganic compound, such as a glass fiber, a carbon fiber, talc, mica or wollastonite, is blended with an aromatic polycarbonate as a reinforcing agent and/or a filler.
However, an aromatic polycarbonate resin composition containing such an inorganic compound possesses a problem that, during the molding, the inorganic compound promotes the decomposition and degradation of the aromatic polycarbonate. Particularly, in the case that a basic inorganic compound, such as talc or mica, is used, there arises a problem that the melt stability of the aromatic polycarbonate is remarkably lowered, so that the physical properties of the material are markedly impaired.
Against the problems, methods for suppressing the lowering of the molecular weight of an aromatic polycarbonate have been proposed, for example, by using a phosphorus compound in combination in JP-A-2-283760 of Patent Document 1, by using an organic acid in combination in JP-A-3-21664 of Patent Document 2, and by using a sulfonic acid phosphonium salt in combination in JP-A-10-60248 of Patent Document 3. However, by these methods, the melt stability, particularly at high temperatures, was still unsatisfactory, so that there is a problem that a range of the molding temperature is limited.
On the other hand, with respect to aromatic polycarbonate resin compositions to be used for office automation machines, and electric and electronic devices, it has been desired to achieve high flame retardancy as well as high stiffness and dimensional precision. In recent years, from the environmental viewpoint, it has been desired to develop a molded article formed of a flame retardant aromatic polycarbonate resin composition which contains neither a bromine compound nor a phosphorus compound as a flame retardant.
JP-A-2002-80709 of Patent Document 4 describes an aromatic polycarbonate resin composition which is obtained by blending an aromatic polycarbonate with an inorganic filler, an organophosphorus compound flame retardant and an organic acid alkali metal salt, which achieves V-0 as measured in accordance with UL94 standard with respect to a test specimen having a thickness of 0.8 mm. However, the resin composition is disadvantageous in that a phosphorus flame retardant is used and the physical properties of a molded article using the resin composition are markedly lowered under high humidity and high temperature.
JP-A-2003-82218 of Patent Document 5 and JP-A-2003-268226 of Patent Document 6 each discloses a resin compositions which is obtained by blending an aromatic polycarbonate with an organic acid metal salt, an alkoxysilane compound, a fluorine-containing polymer, an inorganic filler, and optionally an organosiloxane compound. When the organosiloxane compound is blended, the flame retardancy of the resulting resin composition achieves V-0 as measured in accordance with UL94 standard with respect to a test specimen having a thickness of 0.8 mm. However, since an organosiloxane compound has an insufficient thermal stability, there arise disadvantages that the resin composition is likely to suffer discoloration at a high resin-melting temperature and the amount of volatile components generated increases.                JP-A-2003-82218 of Patent Document 5 and JP-A-2003-268226 of Patent Document 6 each discloses a resin composition which is obtained by blending an aromatic polycarbonate with a fluorine-containing resin and a silicate compound. However, the flame retardancy and melt stability of the resin composition is unsatisfactory.        
As above, in the conventional art, there has not been obtained a thin molded article formed of an aromatic polycarbonate resin composition containing an inorganic compound, which not only exhibits a high flame retardancy in the form of a thin molded article without using a bromine compound or a phosphorus compound as a flame retardant (for example, V-0 as measured in accordance with UL94 standard with respect to a product having a thickness of less than 0.7 mm, or VTM-0 with respect to a product having a thickness of 0.1 mm or less), but also is excellent in melt stability and mechanical strength as a molding material. Therefore, it has been desired to develop such a molded article.
Furthermore, there is an increasing demand for thin sheets and films having flame retardancy and insulating property as inner members for electronic and electric parts.    Patent Document 1: JP-A-2-283760    Patent Document 2: JP-A-3-21664    Patent Document 3: JP-A-10-60248    Patent Document 4: JP-A-2002-80709    Patent Document 5: JP-A-2003-82248    Patent Document 6: JP-A-2003-268226